1. Field of the Invention
This invention relates to a two-way radio communication system and a two-way radio communication method. More specifically, in radio communication systems using the SHF and higher frequency bands such as, for example, radio LANs, radio home links, radio video transmission systems, radio road-to-vehicle communication systems, inter-vehicle communication systems and other such systems utilizing millimeter waves, the present invention relates to a two-way radio communication system and a two-way radio communication method for high-quality, high-speed transmission of digital signals and analog signals.
2. Description of the Prior Art
In JP-A 2001-53640 the present inventors proposed a radio communication system that employs self-heterodyne detection. In this system, part of a local oscillation signal used by the transmitter to frequency-convert a modulated intermediate frequency band signal to a radio frequency band is transmitted by radio simultaneously with the transmission radio frequency, and the receiver then frequency-converts the received radio signal to the modulated intermediate frequency band signal by generating a multiplication product of these two components. However, the above proposal did not provide specific technical details about how to realize the system.
An object of the present invention is to provide a two-way radio communication system and a two-way radio communication method for enabling high-quality, two-way radio communication without the use of a high-quality local oscillation signal.